I am running a ZIP regression and making use of cluster-robust standard errors, whilst including various control variables all on a small experimental sample. However, I've been asked to bootstrap these models because they are underpowered. However, the complex models produce the same results as simple bivariate analyses.

Is it correct that given the use of TYPE=COMPLEX I will have to use replicate weights, but I would also need to generate them first? Second, is this possible the cluster command? Third, is this a fruitful approach to addressing the low power in the complex additional models? Or would you advise something else.

1. Yes. You need replicate weights with bootstrap and complex. You can get that from Mplus by tricking the program: just run a regular regression (the ZIP regression is not available with complex and bootstrap) using this command ANALYSIS: TYPE=COMPLEX; REPSE=BOOTSTRAP; BOOTSTRAP=50; savedata: file is 1.dat; save=repw; Then you will need to run Mplus 50 times for each weight and combine the results manually following section 2.1 https://www.statmodel.com/download/Resampling_Methods5.pdf

2. Yes

3. This is a research question I won't be able to give you a definite answer. I doubt that the answer is yes. I found this discussion enlightening